Oxygen compatible plasma source

ABSTRACT

Described processing chambers may include a chamber housing at least partially defining an interior region of a semiconductor processing chamber. The chamber housing may include a lid. The chamber may include a pedestal configured to support a substrate within a processing region of the chamber. The chamber may also include a first showerhead coupled with an electrical source. The first showerhead may be positioned within the semiconductor processing chamber between the lid and the processing region. The chamber may also include a first dielectric faceplate positioned within the semiconductor processing chamber between the first showerhead and the processing region. The chamber may include a second showerhead coupled with electrical ground and positioned within the semiconductor processing chamber between the first dielectric faceplate and the processing region. The chamber may further include a second dielectric faceplate positioned within the semiconductor processing chamber between the first dielectric faceplate and the second showerhead.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No. 15/285,214, filed Oct. 4, 2016, the contents of which are hereby incorporated by reference in their entirety for all purposes.

TECHNICAL FIELD

The present technology relates to semiconductor systems, processes, and equipment. More specifically, the present technology relates to processing chambers that may include quartz showerheads within the chamber.

BACKGROUND

Integrated circuits are made possible by processes which produce intricately patterned material layers on substrate surfaces. Producing patterned material on a substrate requires controlled methods for removal of exposed material. Chemical etching is used for a variety of purposes including transferring a pattern in photoresist into underlying layers, thinning layers, or thinning lateral dimensions of features already present on the surface. Often it is desirable to have an etch process that etches one material faster than another facilitating, for example, a pattern transfer process. Such an etch process is said to be selective to the first material. As a result of the diversity of materials, circuits, and processes, etch processes have been developed with a selectivity towards a variety of materials.

Etch processes utilize different precursors for etching different materials. For example, some etching processes may utilize a fluorine-containing precursor during the etch process, and other etch processes may utilize a hydrogen-containing precursor during the etch process. These chemicals may have different affinities with different materials, and may cause etching or interaction with the components of the chamber. By adjusting the chamber components or providing coatings, different chambers may utilize different precursors for etching.

Thus, there is a need for improved systems and methods that can be used to perform different etch processes with varying precursors. These and other needs are addressed by the present technology.

SUMMARY

Semiconductor processing systems and methods of the present technology may include semiconductor processing chambers including a chamber housing at least partially defining an interior region of a semiconductor processing chamber. The chamber housing may include a lid. The chambers may include a pedestal configured to support a substrate within a processing region of the chamber. The chambers may also include a first showerhead coupled with an electrical source. The first showerhead may be positioned within the semiconductor processing chamber between the lid and the processing region. The chambers may also include a first dielectric faceplate positioned within the semiconductor processing chamber between the first showerhead and the processing region. The chambers may include a second showerhead coupled with electrical ground and positioned within the semiconductor processing chamber between the first dielectric faceplate and the processing region. The chambers may further include a second dielectric faceplate positioned within the semiconductor processing chamber between the first dielectric faceplate and the second showerhead.

In embodiments the first dielectric faceplate and the second dielectric faceplate may be or include quartz. In exemplary chambers, a dielectric spacer may be positioned between the first dielectric faceplate and the second dielectric faceplate. The dielectric spacer may be or include an annular spacer positioned between and contacting each of the first dielectric faceplate and the second dielectric faceplate. In some embodiments, the first dielectric faceplate, the second dielectric faceplate, and the spacer may define a plasma processing region within the semiconductor processing chamber. The plasma processing region may be configured to at least partially contain a plasma generated between the first showerhead and the second showerhead.

The plasma processing region may be configured to substantially contain the plasma between the first dielectric faceplate and the second dielectric faceplate.

In some embodiments the first showerhead and the second showerhead may be or include a metal oxide. A spacing between the first showerhead and the first dielectric faceplate within the interior region of the semiconductor processing chamber may be less than a Debye length of a plasma formable within the semiconductor processing chamber. In some embodiments, the spacing may be less than or about 0.7 mm. The second dielectric faceplate may define a first plurality of apertures, and the second showerhead may define a second plurality of apertures. In some embodiments, each aperture of the first plurality of apertures may be characterized by a diameter less than a diameter of each aperture of the second plurality of apertures. Each aperture of the first plurality of apertures may be axially aligned with at least a portion of an aperture of the second plurality of apertures in some exemplary chambers. The first plurality of apertures may be characterized by groupings of at least two apertures, and in some embodiments a central axis of each grouping may be axially aligned with a central axis of an aperture of the second plurality of apertures. In embodiments the first plurality of apertures may include at least or about 2,000 apertures, and the second plurality of apertures may include less than or about 1,200 apertures. Additionally, the first plurality of apertures may include at least or about 5,000 apertures, and the second plurality of apertures may include less than or about 1,000 apertures.

The present technology may also include methods of forming an oxygen-containing plasma. The methods may include delivering an oxygen-containing precursor to a semiconductor processing chamber. The semiconductor processing chamber may include a chamber housing at least partially defining an interior region of the semiconductor processing chamber. The chamber housing may include a lid. The chamber may include a pedestal configured to support a substrate within a processing region of the semiconductor processing chamber. The chamber may also include a first showerhead coupled with an electrical source. The first showerhead may be positioned within the semiconductor processing chamber between the lid and the processing region. The chamber may include a first dielectric faceplate positioned within the semiconductor processing chamber between the first showerhead and the processing region. The chamber may include a second showerhead coupled with electrical ground and positioned within the semiconductor processing chamber between the first dielectric faceplate and the processing region. The chamber may also include a second dielectric faceplate positioned within the semiconductor processing chamber between the first dielectric faceplate and the second showerhead. The methods may also include generating a capacitively-coupled plasma from the oxygen-containing precursor between the first showerhead and the second showerhead.

In some embodiments the plasma may be essentially non-existent between the first showerhead and the first dielectric faceplate. Plasma effluents of the generated plasma may flow through the second dielectric faceplate and second showerhead toward the processing region of the semiconductor processing chamber in exemplary methods. In some embodiments, a majority of the plasma effluents may not interact with the second showerhead. In some chambers utilized in the methods, the first showerhead and the second showerhead may include aluminum oxide.

The present technology also includes semiconductor processing chambers. The chambers may include a chamber housing at least partially defining an interior region of the semiconductor processing chamber. The chamber housing may include a lid or lid assembly in embodiments. The chambers may include a pedestal configured to support a substrate within a processing region of the semiconductor processing chamber. The chambers may include a first showerhead coupled with an electrical source. The first showerhead may be positioned within the semiconductor processing chamber between the lid and the processing region, and the first showerhead may be or include a metal oxide. The chambers may also include a first quartz faceplate positioned within the semiconductor processing chamber between the first showerhead and the processing region. The chambers may include a second showerhead coupled with electrical ground and positioned within the semiconductor processing chamber between the first dielectric faceplate and the processing region. In embodiments the first showerhead may be or include a metal oxide. The chambers may also include a second quartz faceplate positioned within the semiconductor processing chamber between the first dielectric faceplate and the second showerhead. The chambers may include a dielectric spacer positioned between and contacting each of the first quartz faceplate and the second quartz faceplate.

Such technology may provide numerous benefits over conventional systems and techniques. For example, oxygen-containing plasmas may be generated, and may exhibit improved recombination characteristics over conventional systems. Additionally, the systems may allow improved protection of chamber components with additional inserts. These and other embodiments, along with many of their advantages and features, are described in more detail in conjunction with the below description and attached figures.

BRIEF DESCRIPTION OF THE DRAWINGS

A further understanding of the nature and advantages of the disclosed technology may be realized by reference to the remaining portions of the specification and the drawings.

FIG. 1 shows a top plan view of an exemplary processing system according to embodiments of the present technology.

FIG. 2 shows a schematic cross-sectional view of an exemplary processing chamber according to embodiments of the present technology.

FIG. 3 shows a bottom plan view of an exemplary showerhead according to embodiments of the disclosed technology.

FIG. 4 shows a plan view of an exemplary faceplate according to embodiments of the disclosed technology.

FIG. 5 shows a cross-sectional view of a processing chamber according to embodiments of the present technology.

FIG. 6A shows a top plan view of an exemplary faceplate according to embodiments of the present technology.

FIG. 6B shows a bottom plan view of an exemplary showerhead and faceplate according to embodiments of the present technology.

FIG. 7A shows a top plan view of an exemplary faceplate according to embodiments of the present technology.

FIG. 7B shows a bottom plan view of an exemplary showerhead according to embodiments of the present technology.

FIG. 8 shows operations of an exemplary method according to embodiments of the present technology.

Several of the figures are included as schematics. It is to be understood that the figures are for illustrative purposes, and are not to be considered of scale unless specifically stated to be of scale. Additionally, as schematics, the figures are provided to aid comprehension and may not include all aspects or information compared to realistic representations, and may include additional or exaggerated material for illustrative purposes.

In the appended figures, similar components and/or features may have the same reference label. Further, various components of the same type may be distinguished by following the reference label by a letter that distinguishes among the similar components. If only the first reference label is used in the specification, the description is applicable to any one of the similar components having the same first reference label irrespective of the letter.

DETAILED DESCRIPTION

The present technology includes systems and components for semiconductor processing including tuned etch processes. When a capacitively-coupled plasma (“CCP”) is formed in a chamber, the plasma effluents may interact with the chamber components involved in generating or containing the plasma. Depending on the material used in these components, the materials may interact beneficially or detrimentally. For example, aluminum or quartz chamber components may chemically interact with fluorine-containing plasma effluents. The plasma particles may chemically recombine on the surface of the materials, and degrade or etch the components themselves. Metal oxide components may not be chemically degraded by fluorine effluents, although hydrogen-containing precursors may remove the oxide coating exposing the underlying material to other etchants.

Metal oxide components may also cause or increase recombination of oxygen plasma effluents as well as hydrogen-containing plasma effluents. This has sometimes been termed as having a high sticking coefficient or ability to cause ions to recombine at the surface. Quartz, on the other hand, may have reduced recombination rates with oxygen-containing plasma effluents, but may not be suitable with fluorine-containing precursors that may degrade the exposed quartz surfaces. Some conventional technologies have dealt with oxygen by attempting to coat aluminum oxide or other metallic surfaces. These techniques may be insufficient for multiple reasons. Initially, materials like quartz may be inferior components for coating due to a coefficient of thermal expansion mismatch with the components being coated, which may cause the quartz liner to crack. Additionally, some of the components may include showerheads or faceplates, which may have patterned apertures that may be difficult to coat. A coating that may not be uniform through the apertures may allow increased recombination of the oxygen-containing plasma effluents.

The present technology may overcome many of these issues by incorporating quartz showerheads within a chamber having CCP components. The quartz showerheads may be positioned to protect the conductive electrodes used to generate the plasma, and may be specifically configured to control the recombination of effluents. For example, the apertures through the showerheads may be aligned with respect to the metallic electrodes to reduce interactions with the metallic electrodes.

Although the remaining disclosure will routinely identify specific etching processes utilizing the disclosed technology, it will be readily understood that the systems and methods are equally applicable to deposition and cleaning processes as may occur in the described chambers. Accordingly, the technology should not be considered to be so limited as for use with etching processes alone.

FIG. 1 shows a top plan view of one embodiment of a processing system 100 of deposition, etching, baking, and curing chambers that may include aspects of present technology. The processing tool 100 depicted in FIG. 1 may contain a plurality of process chambers, 114A-D, a transfer chamber 110, a service chamber 116, an integrated metrology chamber 117, and a pair of load lock chambers 106A-B. The process chambers may include structures or components similar to those described in relation to FIG. 2, as well as additional processing chambers.

To transport substrates among the chambers, the transfer chamber 110 may contain a robotic transport mechanism 113. The transport mechanism 113 may have a pair of substrate transport blades 113A attached to the distal ends of extendible arms 113B, respectively. The blades 113A may be used for carrying individual substrates to and from the process chambers. In operation, one of the substrate transport blades such as blade 113A of the transport mechanism 113 may retrieve a substrate W from one of the load lock chambers such as chambers 106A-B and carry substrate W to a first stage of processing, for example, an etching process as described below in chambers 114A-D. If the chamber is occupied, the robot may wait until the processing is complete and then remove the processed substrate from the chamber with one blade 113A and may insert a new substrate with a second blade (not shown). Once the substrate is processed, it may then be moved to a second stage of processing. For each move, the transport mechanism 113 generally may have one blade carrying a substrate and one blade empty to execute a substrate exchange. The transport mechanism 113 may wait at each chamber until an exchange can be accomplished.

Once processing is complete within the process chambers, the transport mechanism 113 may move the substrate W from the last process chamber and transport the substrate W to a cassette within the load lock chambers 106A-B. From the load lock chambers 106A-B, the substrate may move into a factory interface 104. The factory interface 104 generally may operate to transfer substrates between pod loaders 105A-D in an atmospheric pressure clean environment and the load lock chambers 106A-B. The clean environment in factory interface 104 may be generally provided through air filtration processes, such as HEPA filtration, for example. Factory interface 104 may also include a substrate orienter/aligner (not shown) that may be used to properly align the substrates prior to processing. At least one substrate robot, such as robots 108A-B, may be positioned in factory interface 104 to transport substrates between various positions/locations within factory interface 104 and to other locations in communication therewith. Robots 108A-B may be configured to travel along a track system within enclosure 104 from a first end to a second end of the factory interface 104.

The processing system 100 may further include an integrated metrology chamber 117 to provide control signals, which may provide adaptive control over any of the processes being performed in the processing chambers. The integrated metrology chamber 117 may include any of a variety of metrological devices to measure various film properties, such as thickness, roughness, composition, and the metrology devices may further be capable of characterizing grating parameters such as critical dimensions, sidewall angle, and feature height under vacuum in an automated manner.

Turning now to FIG. 2 is shown a cross-sectional view of an exemplary process chamber system 200 according to the present technology, which may include aspects discussed throughout the disclosure. Chamber 200 may be used, for example, in one or more of the processing chamber sections 114 of the system 100 previously discussed. Generally, the etch chamber 200 may include a first capacitively-coupled plasma source to implement an ion milling operation and a second capacitively-coupled plasma source to implement an etching operation and to implement an optional deposition operation. As explained further below, the chamber may additionally include components configured for plasmas including oxygen-containing precursors. The chamber 200 may include grounded chamber walls 240 surrounding a chuck 250. In embodiments, the chuck 250 may be an electrostatic chuck that clamps the substrate 202 to a top surface of the chuck 250 during processing, though other clamping mechanisms as would be known may also be utilized. The chuck 250 may include an embedded heat exchanger coil 217. In the exemplary embodiment, the heat exchanger coil 217 includes one or more heat transfer fluid channels through which heat transfer fluid, such as an ethylene glycol/water mix, may be passed to control the temperature of the chuck 250 and ultimately the temperature of the substrate 202.

The chuck 250 may include a mesh 249 coupled to a high voltage DC supply 248 so that the mesh 249 may carry a DC bias potential to implement the electrostatic clamping of the substrate 202. The chuck 250 may be coupled with a first RF power source and in one such embodiment, the mesh 249 may be coupled with the first RF power source so that both the DC voltage offset and the RF voltage potentials are coupled across a thin dielectric layer on the top surface of the chuck 250. In the illustrative embodiment, the first RF power source may include a first and second RF generator 252, 253. The RF generators 252, 253 may operate at any industrially utilized frequency, however in the exemplary embodiment the RF generator 252 may operate at 60 MHz to provide advantageous directionality. Where a second RF generator 253 is also provided, the exemplary frequency may be 2 MHz.

With the chuck 250 to be RF powered, an RF return path may be provided by a first showerhead 225, which may include a dual channel showerhead. The first showerhead 225 may be disposed above the chuck to distribute a first feed gas into a first chamber region 284 defined by the first showerhead 225 and the chamber wall 240. As such, the chuck 250 and the first showerhead 225 form a first RF coupled electrode pair to capacitively energize a first plasma 270 of a first feed gas within a first chamber region 284. A DC plasma bias, or RF bias, resulting from capacitive coupling of the RF powered chuck may generate an ion flux from the first plasma 270 to the substrate 202, e.g., Ar ions where the first feed gas is Ar, to provide an ion milling plasma. The first showerhead 225 may be grounded or alternately coupled with an RF source 228 having one or more generators operable at a frequency other than that of the chuck 250, e.g., 13.56 MHz or 60 MHz. In the illustrated embodiment the first showerhead 225 may be selectably coupled to ground or the RF source 228 through the relay 227 which may be automatically controlled during the etch process, for example by a controller (not shown). In disclosed embodiments, chamber 200 may not include showerhead 225 or dielectric spacer 220, and may instead include only baffle 215 and showerhead 210 described further below.

As further illustrated in the figure, the etch chamber 200 may include a pump stack capable of high throughput at low process pressures. In embodiments, at least one turbo molecular pump 265, 266 may be coupled with the first chamber region 284 through one or more gate valves 260 and disposed below the chuck 250, opposite the first showerhead 225. The turbo molecular pumps 265, 266 may be any commercially available pumps having suitable throughput and more particularly may be sized appropriately to maintain process pressures below or about 10 mTorr or below or about 5 mTorr at the desired flow rate of the first feed gas, e.g., 50 to 500 sccm of Ar where argon is the first feedgas. In the embodiment illustrated, the chuck 250 may form part of a pedestal which is centered between the two turbo pumps 265 and 266, however in alternate configurations chuck 250 may be on a pedestal cantilevered from the chamber wall 240 with a single turbo molecular pump having a center aligned with a center of the chuck 250.

Disposed above the first showerhead 225 may be a second showerhead 210. In one embodiment, during processing, the first feed gas source, for example, Argon delivered from gas distribution system 290 may be coupled with a gas inlet 276, and the first feed gas flowed through a plurality of apertures 280 extending through second showerhead 210, into the second chamber region 281, and through a plurality of apertures 282 extending through the first showerhead 225 into the first chamber region 284. An additional flow distributor or baffle 215 having apertures 278 may further distribute a first feed gas flow 216 across the diameter of the etch chamber 200 through a distribution region 218. In an alternate embodiment, the first feed gas may be flowed directly into the first chamber region 284 via apertures 283 which are isolated from the second chamber region 281 as denoted by dashed line 223.

Chamber 200 may additionally be reconfigured from the state illustrated to perform an etching operation. A secondary electrode 205 may be disposed above the first showerhead 225 with a second chamber region 281 there between. The secondary electrode 205 may further form a lid or top plate of the etch chamber 200. The secondary electrode 205 and the first showerhead 225 may be electrically isolated by a dielectric ring 220 and form a second RF coupled electrode pair to capacitively discharge a second plasma 292 of a second feed gas within the second chamber region 281. Advantageously, the second plasma 292 may not provide a significant RF bias potential on the chuck 250. At least one electrode of the second RF coupled electrode pair may be coupled with an RF source for energizing an etching plasma. The secondary electrode 205 may be electrically coupled with the second showerhead 210. In an exemplary embodiment, the first showerhead 225 may be coupled with a ground plane or floating and may be coupled to ground through a relay 227 allowing the first showerhead 225 to also be powered by the RF power source 228 during the ion milling mode of operation. Where the first showerhead 225 is grounded, an RF power source 208, having one or more RF generators operating at 13.56 MHz or 60 MHz, for example, may be coupled with the secondary electrode 205 through a relay 207 which may allow the secondary electrode 205 to also be grounded during other operational modes, such as during an ion milling operation, although the secondary electrode 205 may also be left floating if the first showerhead 225 is powered.

A second feed gas source, such as nitrogen trifluoride, and a hydrogen source, such as ammonia, may be delivered from gas distribution system 290, and coupled with the gas inlet 276 such as via dashed line 224. In this mode, the second feed gas may flow through the second showerhead 210 and may be energized in the second chamber region 281. Reactive species may then pass into the first chamber region 284 to react with the substrate 202. As further illustrated, for embodiments where the first showerhead 225 is a multi-channel showerhead, one or more feed gases may be provided to react with the reactive species generated by the second plasma 292. In one such embodiment, a water source may be coupled with the plurality of apertures 283. Additional configurations may also be based on the general illustration provided, but with various components reconfigured. For example, flow distributor or baffle 215 may be a plate similar to the second showerhead 210, and may be positioned between the secondary electrode 205 and the second showerhead 210.

As any of these plates may operate as an electrode in various configurations for producing plasma, one or more annular or other shaped spacer may be positioned between one or more of these components, similar to dielectric ring 220. Second showerhead 210 may also operate as an ion suppression plate in embodiments, and may be configured to reduce, limit, or suppress the flow of ionic species through the second showerhead 210, while still allowing the flow of neutral and radical species. One or more additional showerheads or distributors may be included in the chamber between first showerhead 225 and chuck 250. Such a showerhead may take the shape or structure of any of the distribution plates or structures previously described. Also, in embodiments a remote plasma unit (not shown) may be coupled with the gas inlet to provide plasma effluents to the chamber for use in various processes.

In an embodiment, the chuck 250 may be movable along the distance H2 in a direction normal to the first showerhead 225. The chuck 250 may be on an actuated mechanism surrounded by a bellows 255, or the like, to allow the chuck 250 to move closer to or farther from the first showerhead 225 as a means of controlling heat transfer between the chuck 250 and the first showerhead 225, which may be at an elevated temperature of 80° C.-150° C., or more. As such, an etch process may be implemented by moving the chuck 250 between first and second predetermined positions relative to the first showerhead 225. Alternatively, the chuck 250 may include a lifter 251 to elevate the substrate 202 off a top surface of the chuck 250 by distance H1 to control heating by the first showerhead 225 during the etch process. In other embodiments, where the etch process is performed at a fixed temperature such as about 90-110° C. for example, chuck displacement mechanisms may be avoided. A system controller (not shown) may alternately energize the first and second plasmas 270 and 292 during the etching process by alternately powering the first and second RF coupled electrode pairs automatically.

The chamber 200 may also be reconfigured to perform a deposition operation. A plasma 292 may be generated in the second chamber region 281 by an RF discharge which may be implemented in any of the manners described for the second plasma 292. Where the first showerhead 225 is powered to generate the plasma 292 during a deposition, the first showerhead 225 may be isolated from a grounded chamber wall 240 by a dielectric spacer 230 so as to be electrically floating relative to the chamber wall. In the exemplary embodiment, an oxidizer feed gas source, such as molecular oxygen, may be delivered from gas distribution system 290, and coupled with the gas inlet 276. In embodiments where the first showerhead 225 is a multi-channel showerhead, any silicon-containing precursor, such as OMCTS for example, may be delivered from gas distribution system 290, and directed into the first chamber region 284 to react with reactive species passing through the first showerhead 225 from the plasma 292. Alternatively the silicon-containing precursor may also be flowed through the gas inlet 276 along with the oxidizer. Chamber 200 is included as a general chamber configuration that may be utilized for various operations discussed in reference to the present technology.

FIG. 3 is a bottom view of a showerhead 325 for use with a processing chamber according to embodiments. Showerhead 325 may correspond with showerhead 225 shown in FIG. 2. Through-holes 365, which may be a view of first fluid channels or apertures 282, may have a plurality of shapes and configurations in order to control and affect the flow of precursors through the showerhead 225. Small holes 375, which may be a view of second fluid channels or apertures 283, may be distributed substantially evenly over the surface of the showerhead, even amongst the through-holes 365, and may provide more even mixing of the precursors as they exit the showerhead than other configurations.

An arrangement for a faceplate according to embodiments is shown in FIG. 4. As shown, the faceplate 400 may include a perforated plate or manifold. The assembly of the faceplate may be similar to the showerhead as shown in FIG. 3, or may include a design configured specifically for distribution patterns of precursor gases. Faceplate 400 may include an annular frame 410 positioned in various arrangements within an exemplary processing chamber, such as the chamber as shown in FIG. 2. On or within the frame may be coupled a plate 420, which may be similar in embodiments to ion suppressor plate 523 as described below. In embodiments faceplate 400 may be a single-piece design where the frame 410 and plate 420 are a single piece of material.

The plate may have a disc shape and be seated on or within the frame 410. The plate may be a conductive material such as a metal including aluminum, as well as other conductive materials that allow the plate to serve as an electrode for use in a plasma arrangement as previously described. The plate may be of a variety of thicknesses, and may include a plurality of apertures 465 defined within the plate. An exemplary arrangement as shown in FIG. 4 may include a pattern as previously described with reference to the arrangement in FIG. 3, and may include a series of rings of apertures in a geometric pattern, such as a hexagon as shown. As would be understood, the pattern illustrated is exemplary and it is to be understood that a variety of patterns, hole arrangements, and hole spacing are encompassed in the design.

The apertures 465 may be sized or otherwise configured to allow fluids to be flowed through the apertures during operation. The apertures may be sized less than about 2 inches in various embodiments, and may be less than or about 1.5 inches, about 1 inch, about 0.9 inches, about 0.8 inches, about 0.75 inches, about 0.7 inches, about 0.65 inches, about 0.6 inches, about 0.55 inches, about 0.5 inches, about 0.45 inches, about 0.4 inches, about 0.35 inches, about 0.3 inches, about 0.25 inches, about 0.2 inches, about 0.15 inches, about 0.1 inches, about 0.05 inches, about 0.04 inches, about 0.035 inches, about 0.03 inches, about 0.025 inches, about 0.02 inches, about 0.015 inches, about 0.01 inches, etc. or less.

In some embodiments faceplate 400 may operate as an ion suppressor that defines a plurality of apertures throughout the structure that are configured to suppress the migration of ionically-charged species out of a chamber plasma region while allowing uncharged neutral or radical species to pass through the ion suppressor into an activated gas delivery region downstream of the ion suppressor. In embodiments, the ion suppressor may be a perforated plate with a variety of aperture configurations. These uncharged species may include highly reactive species that are transported with less reactive carrier gas through the apertures. As noted above, the migration of ionic species through the holes may be reduced, and in some instances completely suppressed. For example, the aspect ratio of the holes, or the hole diameter to length, and/or the geometry of the holes may be controlled so that the flow of ionically-charged species in the activated gas passing through the ion suppressor is reduced.

Turning to FIG. 5 is shown a simplified schematic of processing chamber 500 according to the present technology. The chamber 500 may include any of the components as previously discussed with relation to FIGS. 2-4, and may be configured to house a semiconductor substrate 555 in a processing region 560 of the chamber. The chamber housing 503 may at least partially define an interior region of the chamber. For example, the chamber housing 503 may include lid 502, and may at least partially include any of the other plates or components illustrated in the figure. For example, the chamber components may be included as a series of stacked components with each component at least partially defining a portion of chamber housing 503. The substrate 555 may be located on a pedestal 565 as shown. Processing chamber 500 may include a remote plasma unit (not shown) coupled with inlet 501. In other embodiments, the system may not include a remote plasma unit, and may be configured to receive precursors directly through inlet 501, which may include an inlet assembly for one or more precursors to be distributed to the chamber 500.

With or without a remote plasma unit, the system may be configured to receive precursors or other fluids through inlet 501, which may provide access to a mixing region 511 of the processing chamber. The mixing region 511 may be separate from and fluidly coupled with the processing region 560 of the chamber. The mixing region 511 may be at least partially defined by a top of the chamber of system 500, such as chamber lid 502 or lid assembly, which may include an inlet assembly for one or more precursors, and a distribution device, such as showerhead or faceplate 509 below. Faceplate 509 may be similar to the showerhead or faceplate illustrated in FIG. 4 in disclosed embodiments. Faceplate 509 may include a plurality of channels or apertures 507 that may be positioned and/or shaped to affect the distribution and/or residence time of the precursors in the mixing region 511 before proceeding through the chamber.

For example, recombination may be affected or controlled by adjusting the number of apertures, size of the apertures, or configuration of apertures across the faceplate 509. As illustrated, faceplate 509 may be positioned between the mixing region 511 and the processing region 560 of the chamber, and the faceplate 509 may be configured to distribute one or more precursors through the chamber 500. The chamber of system 500 may include one or more of a series of components that may optionally be included in disclosed embodiments. For example although faceplate 509 is described, in some embodiments the chamber may not include such a faceplate. Additionally, in disclosed embodiments, the precursors that are at least partially mixed in mixing region 511 may be directed through the chamber via one or more of the operating pressure of the system, the arrangement of the chamber components, or the flow profile of the precursors.

Chamber 500 may additionally include a first showerhead 515. Showerhead 515 may have any of the features or characteristics of the plates discussed with respect to FIGS. 3-4. Showerhead 515 may be positioned within the semiconductor processing chamber as illustrated, and may be included or positioned between the lid 502 and the processing region 560. In embodiments, showerhead 515 may be or include a metallic or conductive component that may be a coated, seasoned, or otherwise treated material. Exemplary materials may include metals, including aluminum, as well as metal oxides, including aluminum oxide. Depending on the precursors being utilized, or the process being performed within the chamber, the showerhead may be any other metal that may provide structural stability as well as conductivity as may be utilized.

Showerhead 515 may define one or more apertures 517 to facilitate uniform distribution of precursors through the showerhead. The apertures 517 may be included in a variety of configurations or patterns, and may be characterized by any number of geometries that may provide precursor distribution as may be desired. Showerhead 515, may be electrically coupled with a power source in embodiments. For example, showerhead 515 may be coupled with an RF source 519 as illustrated. When operated, RF source 519 may provide a current to showerhead 515 allowing a capacitively-coupled plasma (“CCP”) to be formed between the showerhead 515 and another component.

Chamber 500 may also include a dielectric faceplate 521. Dielectric faceplate 521 may have any of the features or characteristics of the plates discussed above with respect to FIGS. 3-4. The dielectric faceplate 521 may be positioned within chamber 500 between the showerhead 515 and the processing region 560. Dielectric faceplate 521 may include a plurality of apertures 523 defined through the faceplate. Additionally, chamber 500 may include dielectric faceplate 525. Dielectric faceplate 525 may have any of the features or characteristics of the plates discussed above with respect to FIGS. 3-4, and may be similar or different than dielectric faceplate 521. Dielectric faceplate 525 may define apertures 527 within the structure of the faceplate, and may have or include apertures in a similar or different pattern from dielectric faceplate 521. Dielectric faceplate 525 may be positioned within the chamber between dielectric faceplate 521 and a showerhead 531. Either or both of the dielectric faceplates may be or include an insulative material. In embodiments, the dielectric faceplates 521, 525 may be quartz or any material that may have reduced interaction with oxygen-containing plasma effluents, such as a reduced impact on oxygen recombination as compared to metal oxide components.

Showerhead 531 may be a second showerhead included within the chamber, and may operate as an additional electrode with showerhead 515. Showerhead 531 may include any of the features or characteristics of showerhead 515 discussed previously. In other embodiments certain features of showerhead 531 may diverge from showerhead 515. For example, showerhead 531 may be coupled with an electrical ground 534, which may allow a plasma to be generated between showerhead 515 and showerhead 531 in embodiments. Showerhead 531 may define apertures 533 within the structure to allow precursors or plasma effluents to be delivered to processing region 560.

Chamber 500 optionally may further include a gas distribution assembly 535 within the chamber. In some embodiments, there may be no components between showerhead 531 and processing region 560, and showerhead 531 may allow distribution of precursors or plasma effluents to the processing region 560. The gas distribution assembly 535, which may be similar in aspects to the dual-channel showerheads as previously described, may be located within the chamber above the processing region 560, such as between the processing region 560 and the lid 502, as well as between the processing region 560 and the showerhead 531. The gas distribution assembly 535 may be configured to deliver both a first and a second precursor into the processing region 560 of the chamber. In embodiments, the gas distribution assembly 535 may at least partially divide the interior region of the chamber into a remote region and a processing region in which substrate 555 is positioned.

Although the exemplary system of FIG. 5 includes a dual-channel showerhead, it is understood that alternative distribution assemblies may be utilized that maintain a precursor fluidly isolated from species introduced through inlet 501. For example, a perforated plate and tubes underneath the plate may be utilized, although other configurations may operate with reduced efficiency or not provide as uniform processing as the dual-channel showerhead as described. By utilizing one of the disclosed designs, a precursor may be introduced into the processing region 560 that is not previously excited by a plasma prior to entering the processing region 560, or may be introduced to avoid contacting an additional precursor with which it may react. Although not shown, an additional spacer may be positioned between the showerhead 531 and the gas distribution assembly 535, such as an annular spacer, to isolate the plates from one another. In embodiments in which an additional precursor may not be included, the gas distribution assembly 535 may have a design similar to any of the previously described components, and may include characteristics similar to the plates illustrated in FIGS. 3-4.

In embodiments, gas distribution assembly 535 may include an embedded heater 539, which may include a resistive heater or a temperature controlled fluid, for example. The gas distribution assembly 535 may include an upper plate and a lower plate. The plates may be coupled with one another to define a volume 537 between the plates. The coupling of the plates may be such as to provide first fluid channels 540 through the upper and lower plates, and second fluid channels 545 through the lower plate. The formed channels may be configured to provide fluid access from the volume 537 through the lower plate, and the first fluid channels 540 may be fluidly isolated from the volume 537 between the plates and the second fluid channels 545. The volume 537 may be fluidly accessible through a side of the gas distribution assembly 535, such as channel 223 as previously discussed. The channel may be coupled with an access in the chamber separate from the inlet 501 of the chamber 500.

An additional optional component that may or may not be included in the chamber 500 is faceplate 547, which may also be a dielectric, such as quartz. Faceplate 547 may provide similar functionality, and include similar characteristics, as faceplates 521, 525, and may be used in an ion milling or ion etching operation as explained above. Faceplate 547 may include apertures 549 defined through the structure of the faceplate. Any of the faceplates may have aperture characteristics, patterns, or sizing as discussed throughout this application. The chamber 500 may also include a chamber liner 551, which may protect the walls of the chamber from plasma effluents as well as material deposition, for example. The liner may be or may include a conductive material, and in embodiments may be or include an insulative material. In some embodiments, the chamber walls or liner may operate as an additional electrical grounding source.

A spacer 529 may be positioned between the first dielectric faceplate 521 and the second dielectric faceplate 525. The spacer may be a dielectric, and may be quartz or any other dielectric material providing insulation between two components. In embodiments, spacer 529 may be an annular spacer positioned between the two faceplates and contacting both dielectric faceplate 521 and dielectric faceplate 525.

In some embodiments, a plasma as described earlier may be formed in a region of the chamber defined between two or more of the components previously discussed. For example, a plasma region such as a plasma processing region 550, may be formed between showerhead 515 and showerhead 531. Spacer 529 may maintain the two components electrically isolated from one another in order to allow a plasma field to be formed. Showerhead 515 may be electrically charged while showerhead 531 may be grounded or DC biased to produce a plasma field within the region defined between the plates. The plates may additionally be coated or seasoned in order to minimize the degradation of the components between which the plasma may be formed. The plates may additionally include compositions that may be less likely to degrade or be affected including ceramics, metal oxides, or other conductive materials.

Operating a conventional capacitively-coupled plasma (“CCP”) with certain precursors such as oxygen or hydrogen may impact the control over plasma recombination as previously discussed. For example, components may be or include an aluminum oxide coating, for example, or may be aluminum. Aluminum oxide may increase the recombination of oxygen ions and radicals upon contact, which may cause issues with uniformity and control of the plasma effluents, which may impact the substrate being worked. Accordingly, to protect the plasma effluents, which may be oxygen-containing effluents or hydrogen-containing effluents, for example, quartz plates 521, 525 may be included in the plasma processing region 550. In other embodiments, plates 521, 525 may be or include materials other than quartz including other dielectric materials such as ceramics or non-metallic materials that may exhibit low conductivity.

The plasma processing region 550 may be defined in part between the first showerhead 515 and the second showerhead 531. Additionally, the first dielectric faceplate 521, the second dielectric faceplate 525, which may both be quartz, and the spacer 529 may define plasma processing region 550 within the semiconductor processing chamber. These components may be at least partially configured to at least partially contain a plasma generated between the first showerhead 515 and the second showerhead 531. In some embodiments, these components may be spaced, positioned, or configured to substantially contain the plasma between the first dielectric faceplate 521, and the second dielectric faceplate 525.

The spacing between each of the first showerhead 515 and second showerhead 531 with respect to the first dielectric faceplate 521 and the second dielectric faceplate 525 may impact the scope of the plasma processing region 550. For example, plasma may be capable of being generated in the entire space between the electrodes generating the plasma, such as showerhead 515 and showerhead 531. Were this to occur in embodiments, the oxygen-containing precursor may be ionized between the first showerhead 515 and the first dielectric faceplate 521. The ions or radicals may then contact the showerhead 515, and begin recombination at a higher rate than if maintained between quartz components, for example. A similar phenomenon may occur between the second showerhead 531 and the second dielectric faceplate 525. However, the first dielectric faceplate 521 and the second dielectric faceplate 525 may be positioned to adjust the plasma processing region to reduce, prevent, or substantially prevent plasma generation at the surfaces of the electrodes, or showerhead 515 and showerhead 531.

For example, depending on certain characteristics including operating conditions such as temperature, pressure, and generating frequency, a plasma may be generated in regions having a length greater than a Debye length where the plasma may remain on average electrically neutral or quasineutral. In regions with distances less than a Debye length, this may not be achieved, and a plasma may not strike. Accordingly, by maintaining a distance between the first showerhead 515 and the first dielectric spacer 521 of less than a Debye length, plasma may not form between the components. Similarly, the distance between the second showerhead 531 and the second dielectric faceplate 525 may also be maintained below a Debye length in order to limit plasma from generating within this region. Thus, in embodiments, both distances may be maintained below a Debye length, and the plasma may be substantially or essentially contained within the region defined between the first dielectric faceplate 521 and the second dielectric faceplate 525.

In some embodiments in which an oxygen-containing plasma is being generated within the plasma processing region 550, based on the operating pressure and frequency, for example, a Debye length may be less than or about 25 mm. This length may be between axially oriented positions on the two plates within the interior region of the semiconductor processing chamber. For example, the plates may contact one another at an exterior edge of the plates, but may maintain the distance across the interior region of the processing chamber. In embodiments, the distance between the showerheads 515, 531 and their respective quartz faceplates 521, 525 may be maintained below or about 25 mm. In other embodiments, the distance may be maintained below or about 20 mm, below or about 15 mm, below or about 12 mm, below or about 10 mm, below or about 8 mm, below or about 6 mm, below or about 5 mm, below or about 4 mm, below or about 3 mm, below or about 2 mm, below or about 1 mm, below or about 0.9 mm, below or about 0.8 mm, below or about 0.7 mm, below or about 0.6 mm, below or about 0.5 mm, below or about 0.4 mm, below or about 0.3 mm, below or about 0.2 mm, below or about 0.1 mm, or at about 0 mm in which the showerhead and quartz faceplate are in contact. The components may be maintained at a distance between any of these distances listed or within any smaller range of the defined ranges. For example, a showerhead and quartz plate may be maintained between about 0 mm and about 1 mm in embodiments, or between about 0.1 mm and about 0.6 mm.

Either showerhead 515 or showerhead 531 may not be in direct contact with dielectric faceplate 521 or dielectric faceplate 525, for example. Although quartz may exhibit acceptable characteristics during temperature cycling, direct contact between a quartz faceplate and an aluminum or aluminum oxide showerhead may cause cracking of the quartz faceplate. Accordingly, in embodiments in which no space is to be developed between the showerheads 515, 531 and the dielectric faceplates 521, 525, a material may be positioned in direct contact with the showerhead and dielectric faceplate that may absorb thermally-induced changes in either material, or provide a buffer between the two components.

In operation during an exemplary process that may be performed in chamber 500 or similar chambers, an oxygen-containing plasma may be generated between dielectric faceplate 521 and dielectric faceplate 525. Effluents produced may travel through the interior region of chamber 500 towards processing region 560. To travel from plasma processing region 550 to processing region 560, the plasma effluents, which may include oxygen-containing effluents, may pass through not only dielectric faceplate 525, but also showerhead 531. Accordingly, showerhead 531, which may be a conductive material, such as aluminum, which may have a coating such as aluminum oxide, may interact with the plasma effluents. In embodiments the apertures or configurations of showerhead 531 and/or dielectric faceplate 525 may be adjusted to accommodate the structure and reduce the impact of the aluminum oxide and aluminum on the generated plasma effluents.

Turning to FIG. 6A is shown a top plan view of an exemplary dielectric faceplate 600 according to embodiments of the present technology. As illustrated, faceplate 600 may include a dielectric material 610, which may be quartz in embodiments. Additionally, dielectric faceplate may be either of dielectric faceplates 521, 525 in embodiments. The dielectric faceplate 600 may include any of the components or characteristics of the plates discussed with respect to FIGS. 3-4 above. Dielectric faceplate 600 may include apertures 620 defined through the structure of the faceplate, and the faceplate may define a first plurality of apertures in embodiments. The apertures as included within the faceplate 600 may be characterized in groupings as illustrated. The groupings may include at least two apertures in embodiments, and may include at least or about 3 apertures per grouping, at least or about 4 apertures per grouping, at least or about 5 apertures per grouping, at least or about 6 apertures per grouping, at least or about 7 apertures per grouping, at least or about 8 apertures per grouping, at least or about 9 apertures per grouping, at least or about 10 apertures per grouping, at least or about 15 apertures per grouping, at least or about 20 apertures per grouping, at least or about 50 apertures per grouping, at least or about 100 apertures per grouping, at least or about 130 apertures per grouping, at least or about 160 apertures per grouping, at least or about 200 apertures per grouping, or more depending on factors including the size of the faceplate, and the size of apertures and association of apertures in the corresponding showerhead.

Additionally, the sizing of the apertures 620 may be used to affect or control plasma recombination. Each aperture 620 may be characterized by a diameter of greater than or about 0.1 mm in embodiments, and may be characterized by a diameter of greater than or about 0.15 mm, greater than or about 0.2 mm, greater than or about 0.25 mm, greater than or about 0.3 mm, greater than or about 0.35 mm, greater than or about 0.4 mm, greater than or about 0.45 mm, greater than or about 0.5 mm, greater than or about 0.55 mm, greater than or about 0.6 mm, greater than or about 0.65 mm, greater than or about 0.7 mm, greater than or about 0.75 mm, greater than or about 0.8 mm, greater than or about 0.85 mm, greater than or about 0.9 mm, greater than or about 0.95 mm, greater than or about 1.0 mm, greater than or about 1.25 mm, greater than or about 1.5 mm, greater than or about 1.75 mm, greater than or about 2 mm, greater than or about 2.5 mm, or greater.

Diameter is intended to cover the width across the aperture or normal to a central axis of the aperture, such as in non-circular apertures, for example, or apertures characterized by changing geometry throughout the height of the aperture. Each aperture may also be characterized by a diameter of between about 0.1 mm and about 1 mm, between about 0.3 mm and about 0.8 mm, or between about 0.4 mm to about 0.5 mm in embodiments. In embodiments, the dielectric faceplate may be characterized by greater than or about 1,000 apertures throughout the faceplate, and each aperture may be incorporated within specific groupings. Additionally, the faceplate may be characterized by greater than or about 2,000 apertures, greater than or about 3,000 apertures, greater than or about 4,000 apertures, greater than or about 5,000 apertures, greater than or about 6,000 apertures, greater than or about 7,000 apertures, greater than or about 8,000 apertures, greater than or about 9,000 apertures, greater than or about 10,000 apertures or more apertures depending on the aperture dimensions as well as the plate dimensions and arrangement of apertures in groupings, for example. In other embodiments, faceplate 600 may include less than any of the numbers or sizes of apertures listed, or a smaller range within any of the listed ranges.

FIG. 6B shows a bottom plan view of an exemplary showerhead 650 and faceplate 600 according to embodiments of the present technology. The components may be views of showerhead 531 and dielectric faceplate 525 previously discussed. As illustrated, showerhead 650 may include a plate 660, which may be a conductive material. Showerhead 650 may operate within a chamber as a ground electrode in a CCP arrangement. Showerhead 650 may also define a plurality of apertures 670, which may be a second plurality of apertures. Apertures 670 may be larger than first apertures 620, each of which may be characterized by a diameter less than a diameter of each aperture of the second plurality of apertures 670.

Apertures 670 may be characterized by a diameter greater than a diameter of an individual aperture 620 of faceplate 600. In embodiments, apertures 670 may each be characterized by a diameter greater than or about 1 mm, greater than or about 2 mm, greater than or about 3 mm, greater than or about 4 mm, greater than or about 5 mm, greater than or about 6 mm, greater than or about 7 mm, greater than or about 8 mm, greater than or about 9 mm, greater than or about 10 mm, greater than or about 11 mm, greater than or about 12 mm, greater than or about 13 mm, greater than or about 15 mm, greater than or about 20 mm, or greater depending on the size of the showerhead and the number of associated apertures from faceplate 600. Additionally, showerhead 650 may define at least about 200 apertures 670 through its structure, and in embodiments may define at least about 300 apertures, at least about 400 apertures, at least about 500 apertures, at least about 600 apertures, at least about 700 apertures, at least about 800 apertures, at least about 900 apertures, at least about 1,000 apertures, at least about 1,100 apertures, at least about 1,200 apertures, at least about 1,300 apertures, at least about 1,500 apertures, at least about 2,000 apertures, or more apertures depending on the size of the apertures as well as the plate through which they are defined. In other embodiments, showerhead 650 may include less than any of the numbers or sizes of apertures listed, or a smaller range within any of the listed ranges.

Apertures 670 may be configured in a pattern relative to a pattern in which the first plurality of apertures 620 may be configured. For example, each aperture of the first plurality of apertures 620 may be axially aligned with at least a portion of an aperture of the second plurality of apertures 670. In this example, an aperture of the first plurality of apertures 620 may be aligned with or about an aperture of the second plurality of apertures 670 so that at least a portion of the aperture of the first plurality of apertures 620 extends towards or overlaps the space defined by the aperture of the second plurality of apertures 670. Additionally, in embodiments in which the first plurality of apertures 620 are incorporated in groupings, a central axis of each grouping of the first plurality of apertures 620 may be axially aligned with a central axis of an aperture of the second plurality of apertures 670. For example, as illustrated in the figure, each aperture 670 may be aligned with a central axis of a grouping of apertures 620.

In embodiments, each aperture 670 may be aligned with a grouping of at least about 3 apertures of the first plurality of apertures 620. Additionally, each aperture 670 may be aligned with a grouping of at least about 4 apertures of the first plurality of apertures 620, at least about 5 apertures, at least about 6 apertures, at least about 7 apertures, at least about 8 apertures, at least about 9 apertures, at least about 10 apertures, at least about 11 apertures, at least about 12 apertures, at least about 13 apertures, at least about 14 apertures, at least about 15 apertures, at least about 20 apertures, at least about 50 apertures, at least about 75 apertures, at least about 100 apertures, at least about 125 apertures, at least about 150 apertures, at least about 175 apertures, at least about 200 apertures, or more apertures depending on the size of apertures 620, the size of apertures 670, as well as the showerhead and faceplate dimensions, for example. Although discussed as one showerhead and faceplate pairing, it is to be understood that the combination may be either or both of showerheads 515, 531 and dielectric faceplates 521, 525 as previously discussed. Additionally, the first showerhead/faceplate combination may be characterized by a first aperture configuration, while the second showerhead/faceplate combination may be characterized by a second aperture configuration.

In many CCP electrode flow-through configurations, where precursors may pass through at least one electrode to interact with a substrate, the aperture sizing of the electrode, such as showerhead 531, for example, may impact the operations. For example, as aperture size increases, plasma leakage may occur, and it may become more difficult to control the plasma or effluents being produced. Additionally, plasma particles may leak through the showerhead and interact with the substrate, which may cause sputtering or other damage. Accordingly, many conventional CCP systems may be limited to aperture sizing of less than a few millimeters or less than a millimeter. However, the present systems may utilize the faceplates, such as quartz faceplates, to control the plasma by utilizing smaller holes in the faceplate. In this way, the apertures within the showerhead may be increased beyond limits that may occur with conventional systems, and may reduce interactions with the plasma effluents. Additionally, despite the increased aperture sizing, the showerheads may still operate acceptably as an electrode by which plasma may be formed.

Turning to FIG. 7A is shown a top plan view of an exemplary faceplate 700 according to embodiments of the present technology. Faceplate 700 may include or be characterized by any of the features or characteristics of any faceplate previously discussed. Faceplate 700 may include a dielectric material 710 in which apertures 720 have been defined. Apertures 720 may be or include any of the sizing or grouping characteristics previously discussed. Additionally illustrated are exemplary apertures 730 of a showerhead with which faceplate 700 may be coupled. Such a configuration may resemble a top view of dielectric faceplate 525 and showerhead 531, for example, but may also illustrate characteristics compatible with dielectric faceplate 521 and showerhead 515. Apertures 730 are illustrated as hidden as they may not be visible from any particular aperture 720 of faceplate 700.

For example, in embodiments, the apertures 720 may be staggered from showerhead apertures, such as apertures 730 so that there is no line of sight from any aperture 720 to any aperture 730. Many possible configurations are possible for defining apertures in faceplate 700 to produce such an effect. For example, apertures 720 may be included in a pattern across the faceplate 700 to prevent any orientation or alignment with any aperture 730 of a corresponding showerhead. Additionally, apertures 720 may be included in groupings that extend about a relative perimeter of an aperture 730 of a corresponding showerhead. For example, as illustrated, apertures 720 are included in groupings of about 6 apertures about a corresponding location of an aperture 730 for a corresponding showerhead. Any of the groupings previously discussed, or aperture configurations, may similarly be applied to this arrangement, and are encompassed by the present technology.

FIG. 7B shows a bottom plan view of an exemplary showerhead 750 according to embodiments of the present technology. Showerhead 750 may be the corresponding showerhead having apertures 730 illustrated with faceplate 700, for example. Showerhead 750 may be characterized by any of the configurations or characteristics of any of the previously discussed showerheads in embodiments. As illustrated, apertures 730 may not provide line of sight to any apertures of faceplate 700, which may have apertures staggered about apertures 730 of the corresponding faceplate 700. Although in this example no apertures of a corresponding faceplate are shown, in other embodiments any percentage or portion of apertures of a faceplate may be visible or have line of sight with any aperture 730 of showerhead 750.

The chambers, faceplates, and showerheads described above may be used in one or more methods. FIG. 8 shows operations of an exemplary method 800 which may be performed in the chambers previously discussed, such as one or more versions of chamber 500, or may be performed in a chamber including any of the faceplates or showerheads previously discussed.

As illustrated, the method may include flowing a precursor into the chamber at operation 805. In embodiments the precursor may be or include oxygen, for example, and may also include hydrogen, an inert precursor, or some other precursor useable in semiconductor processing. In some embodiments, the precursor or precursors delivered to the chamber may be or include one or more halogen-containing precursors, although in other embodiments, the precursors may be free of one or more halogen-containing precursors. For example, in embodiments, the precursors may be free of fluorine-containing precursors. However, additional precursors may be delivered into a chamber, such as chamber 500 via the gas distribution assembly 535, which may allow the faceplates, which may be quartz, to be protected from a fluorine-containing precursor, or other precursor.

At operation 810, a capacitively-coupled plasma (“CCP”) may be generated from the precursors delivered into the chamber, such as oxygen or an oxygen-containing precursor. In embodiments, the plasma may be generated between electrodes of the CCP, which may be showerheads, such as showerheads 515, 531, for example, as previously described. The plasma may be contained or substantially contained between quartz faceplates, which may be positioned between electrodes used to generate the CCP. In embodiments, the electrodes may be conductive showerheads, and may be or include aluminum or aluminum oxide, for example. Additionally, plasma may not be formed, or may be essentially non-existent between a first showerhead and a first dielectric faceplate in embodiments, such as showerhead 515 and dielectric faceplate 521, for example.

Plasma effluents that have been formed may be flowed from the plasma processing region at operation 815. The effluents may be flowed to or towards a processing region in which a semiconductor substrate is housed. The effluents may be flowed through one or more components of the chamber, such as chamber 500, and may be flowed through a dielectric faceplate and/or a showerhead. The showerhead may be an electrode by which the CCP was generated, such as a ground electrode in embodiments. In some embodiments, the plasma effluents may not interact or may substantially not interact with the electrode through which they may be flowed. For example, apertures of the electrode, such as showerhead 531, for example, may be sized and/or configured to limit their interaction with the plasma effluents formed. In embodiments, the electrode may have less interaction with the plasma effluents than in a system in which a dielectric faceplate is not included in coordination with the showerhead, such as in any of the arrangements previously described. In some embodiments, the amount of interaction may be 10% less than a system in which a dielectric faceplate is not included in coordination with the showerhead. Additionally, the amount of interaction may be 20% less, 30% less, 40% less, 50% less, 60% less, 70% less, 80% less, 90% less, or 100% less than a system in which a dielectric faceplate is not included in coordination with the showerhead. A system including the components of the present technology may better control recombination of plasma effluents, which may include oxygen, for example.

In the preceding description, for the purposes of explanation, numerous details have been set forth in order to provide an understanding of various embodiments of the present technology. It will be apparent to one skilled in the art, however, that certain embodiments may be practiced without some of these details, or with additional details.

Having disclosed several embodiments, it will be recognized by those of skill in the art that various modifications, alternative constructions, and equivalents may be used without departing from the spirit of the embodiments. Additionally, a number of well-known processes and elements have not been described in order to avoid unnecessarily obscuring the present technology. Accordingly, the above description should not be taken as limiting the scope of the technology.

Where a range of values is provided, it is understood that each intervening value, to the smallest fraction of the unit of the lower limit, unless the context clearly dictates otherwise, between the upper and lower limits of that range is also specifically disclosed. Any narrower range between any stated values or unstated intervening values in a stated range and any other stated or intervening value in that stated range is encompassed. The upper and lower limits of those smaller ranges may independently be included or excluded in the range, and each range where either, neither, or both limits are included in the smaller ranges is also encompassed within the technology, subject to any specifically excluded limit in the stated range. Where the stated range includes one or both of the limits, ranges excluding either or both of those included limits are also included.

As used herein and in the appended claims, the singular forms “a”, “an”, and “the” include plural references unless the context clearly dictates otherwise. Thus, for example, reference to “a layer” includes a plurality of such layers, and reference to “the precursor” includes reference to one or more precursors and equivalents thereof known to those skilled in the art, and so forth.

Also, the words “comprise(s)”, “comprising”, “contain(s)”, “containing”, “include(s)”, and “including”, when used in this specification and in the following claims, are intended to specify the presence of stated features, integers, components, or operations, but they do not preclude the presence or addition of one or more other features, integers, components, operations, acts, or groups. 

1. A semiconductor processing chamber comprising: a first showerhead coupled with an electrical source; a first dielectric faceplate positioned within the semiconductor processing chamber between the first showerhead and a processing region; a second showerhead coupled with electrical ground and positioned within the semiconductor processing chamber between the first dielectric faceplate and the processing region; and a second dielectric faceplate positioned within the semiconductor processing chamber between the first dielectric faceplate and the second showerhead.
 2. The semiconductor processing chamber of claim 1, wherein the first dielectric faceplate and the second dielectric faceplate comprise quartz.
 3. The semiconductor processing chamber of claim 1, further comprising a dielectric spacer positioned between the first dielectric faceplate and the second dielectric faceplate.
 4. The semiconductor processing chamber of claim 3, wherein the dielectric spacer comprises an annular spacer positioned between and contacting each of the first dielectric faceplate and the second dielectric faceplate.
 5. The semiconductor processing chamber of claim 4, wherein the first dielectric faceplate, the second dielectric faceplate, and the spacer define a plasma processing region within the semiconductor processing chamber, wherein the plasma processing region is configured to at least partially contain a plasma generated between the first showerhead and the second showerhead.
 6. The semiconductor processing chamber of claim 5, wherein the plasma processing region is configured to substantially contain the plasma between the first dielectric faceplate and the second dielectric faceplate.
 7. The semiconductor processing chamber of claim 1, wherein the first showerhead and the second showerhead comprise a metal oxide.
 8. The semiconductor processing chamber of claim 1, wherein a spacing between the first showerhead and the first dielectric faceplate within an interior region of the semiconductor processing chamber is less than a Debye length of a plasma formable within the semiconductor processing chamber.
 9. The semiconductor processing chamber of claim 8, wherein the spacing is less than or about 0.7 mm.
 10. The semiconductor processing chamber of claim 1, wherein the second dielectric faceplate defines a first plurality of apertures, and wherein the second showerhead defines a second plurality of apertures, and wherein each aperture of the first plurality of apertures is characterized by a diameter less than a diameter of each aperture of the second plurality of apertures.
 11. The semiconductor processing chamber of claim 10, wherein each aperture of the first plurality of apertures is axially aligned with at least a portion of an aperture of the second plurality of apertures.
 12. The semiconductor processing chamber of claim 10, wherein the first plurality of apertures are characterized by groupings of at least two apertures, and wherein a central axis of each grouping is axially aligned with a central axis of an aperture of the second plurality of apertures.
 13. The semiconductor processing chamber of claim 10, wherein the first plurality of apertures comprises at least or about 2,000 apertures, and wherein the second plurality of apertures comprises less than or about 1,200 apertures.
 14. The semiconductor processing chamber of claim 13, wherein the first plurality of apertures comprises at least or about 5,000 apertures, and wherein the second plurality of apertures comprises less than or about 1,000 apertures.
 15. A method of forming an oxygen-containing plasma, the method comprising: delivering an oxygen-containing precursor to a semiconductor processing chamber, the semiconductor processing chamber including: a chamber housing at least partially defining an interior region of the semiconductor processing chamber, wherein the chamber housing comprises a lid, a pedestal configured to support a substrate within a processing region of the semiconductor processing chamber, a first showerhead coupled with an electrical source, wherein the first showerhead is positioned within the semiconductor processing chamber between the lid and the processing region, a first dielectric faceplate positioned within the semiconductor processing chamber between the first showerhead and the processing region, a second showerhead coupled with electrical ground and positioned within the semiconductor processing chamber between the first dielectric faceplate and the processing region, and a second dielectric faceplate positioned within the semiconductor processing chamber between the first dielectric faceplate and the second showerhead; and generating a capacitively-coupled plasma from the oxygen-containing precursor between the first showerhead and the second showerhead.
 16. The method of forming an oxygen-containing plasma of claim 15, wherein the plasma is essentially non-existent between the first showerhead and the first dielectric faceplate.
 17. The method of forming an oxygen-containing plasma of claim 15, wherein plasma effluents of the generated plasma flow through the second dielectric faceplate and second showerhead toward the processing region of the semiconductor processing chamber.
 18. The method of forming an oxygen-containing plasma of claim 17, wherein a majority of the plasma effluents do not interact with the second showerhead.
 19. The method of forming an oxygen-containing plasma of claim 15, wherein the first showerhead and the second showerhead comprise aluminum oxide.
 20. A semiconductor processing chamber comprising: a first showerhead coupled with an electrical source; a dielectric faceplate positioned within the semiconductor processing chamber between the first showerhead and a processing region, wherein the dielectric faceplate defines a first plurality of apertures; and a second showerhead coupled with electrical ground and positioned within the semiconductor processing chamber between the dielectric faceplate and the processing region, wherein the second showerhead defines a second plurality of apertures each larger than an aperture of the first plurality of apertures, and wherein each aperture of the first plurality of apertures is axially aligned with a portion of an aperture of the second plurality of apertures. 